1. Field of the Invention
This invention relates to an electronic medical instrumentation system and, more specifically, pertains to a real time breath-by-breath cardiopulmonary exercise system for assessing the performance of the heart and lungs during exercise.
2. Description of the Prior Art
Prior art exercise monitors and systems have failed to provide a breath-by-breath analysis of an individual's heart and lungs during exercise.
The earliest prior art exercise monitors involved an individual's exhaling or expiring into a bag, such as a Douglas bag or weather balloon, for manual collection of expired gases. A laboratory technician would then, at the end of an exercise period, use a gas analyzer to analyze the gases in the bag to determine the expired CO.sub.2 and O.sub.2. Further, analysis of expired volume involved dumping the bag contents into a gasometer (Tissot) and quantifying the volume of gas expired during the collection period. From this raw data, numerous hand calculation were required in order to determine a few of the possible cardiopulmonary parameters.
Another prior art device is a mixing chamber which is used to gather an individual's expired breath and is spot sampled by gas analyzers at periodic intervals to determine an average expired gas concentration. Expired volume is measured by either the bag method previously described or by another volume transducing device such as a turbine.
All of the prior art devices fail to provide a breath-by-breath analysis to resolve the important first breaths of expiration during an exercise period. The prior art devices fail to account for minute intervals typically present in disability and rehabilitation evaluations. Hence, a base line for standard assessment of that individual's performance and parameters of the heart and lungs is not made available.
The cardiopulmonary exercise system of the present invention is a real-time distributed processing system which analyzes each breath, begining with the first breath and continuing over a specified time interval, and allows the monitoring of an individual either while at rest or during stress.